Didn't read the whole thread so im not sure if this has been said. I was having problems with down boxes/rails ect. all year, and then i got a tip about doing a smaller pop with just my legs rather than using arms a bunch. (before i was like kinda throwing my arms up while popping). Also look at the end of it and plan what you're going to do at the end (switch off, back to regular etc.) so you have something to commit to.
Spark notes: use just your legs (might seem obvious but apparently i was doing it) dont throw arms with your pop. look at the end. COMMIT